Cells Flashcards
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Nucleus simple function
Genetic information is stored on chromosomes, which is made up of DNA
Cytoplasm simple function
Site of metabolic reactions
Cell Membrane simple function
Partially permeable - controls the entry and exit of substances in a cell.
Cell wall simple function
Provides protection and support. Prevents plant cells from bursting.
Vacuole simple function
Contains cell sap which helps to maintain the shape of the cell.
Chloroplasts simple function
Contain chlorophyll which absorbs light energy for photosynthesis
Mitochondria simple function
Site of aerobic respiration
Ribosomes simple function
Site of protein synthesis
Mitochondria detailed explanation
- Present in almost all cells except for prokaryotic cells
- Site of aerobic respiration
- The higher the rate of metabolism of the cell, the larger numbers of mitochondria required in order to provide sufficient energy to the cell
Rough Endoplasmic Reticulum detailed explanation
- Present in almost all cells except for prokaryotic cells
- A network of membranes that runs through the cytoplasm
- Transports proteins made by ribosomes
Ribosomes detailed explanation
- Present in all cells
- Site of protein synthesis
- Can be scattered around the cytoplasm
- Can be bound to the surface of rough endoplasmic reticulum
- Use genetic information stored on chromosomes to make these proteins
Vesicles (in Animal Cells) detailed explanation
Animal cells have small membrane-bound spaces known as Vesicles that can contain food and water
What are Ciliated Epithelial Cells
- Specialised Animal Cell
- Found in the inner linings of the respiratory tract and oviducts
- Have projections called Cilia which can move
- Function is the movement of mucus in the trachea and bronchi
- Cilia helps to move the mucus (which contains trapped germs and dirt) away from the lungs and towards the nose and mouth
What are Red Blood Cells
- Specialised Animal Cell
- Transports oxygen to all parts of the body
- Has no nucleus which allows more space for haemoglobin which transports oxygen
- Has a disc shape which allows for more surface area for absorption of oxygen
- Flexible so that it can squeeze through narrow capillaries
What are Nerve Cells/Neurons
- Specialised Animal Cell
- Conducts nerve impulses
- Has longest cells in the body which aids in transfer of impulses over long distances
- Dendrites and axon endings are branched, which allow for impulses to be picked up from multiple receiver cells and for a faster transmission of impulses between neurons.
What are Sperm Cells
- Specialised Animal Cell
- Function is reproduction
- Flagellum allows sperm cell to swim to the egg cell
- Middle piece contains mitochondria to provide the energy for the swimming
- The acrosome is a vesicle that contains hydrolytic enzymes that can penetrate the layer of jelly surrounding the egg cell.
What are Egg Cells
- Specialised Animal Cell
- Function is reproduction
- It is a large cell with lots of cytoplasm to provide nutrition for the growing zygote until implantation and attachment to the placenta in the uterus takes place
- Jelly coat surrounding the cell membrane hardens after the egg is fertilised to prevent other sperm cells from entering the egg cell
What are Root Hair Cells
- Specialised Plant Cell
- Function is absorption of water and minerals
- Projections called root hair increase the surface area for the absorption of water and mineral salts
What are Palisade Mesophyll Cells
- Specialised Plant Cell
- Function is photosynthesis
- Long cells which are closely packed together and found just under the upper epidermis ensure maximum exposure to sunlight
- Contain lots of chloroplasts, which in turn contain chlorophyll that traps light energy for photosynthesis
What are Xylem Vessels
- Specialised Plant Cell
- Function is the conduction of water and support
- Mature xylem vessels don’t have a nucleus or cytoplasm to allow more space for the conduction of water
- This also ensures that the cells themselves don’t use up the water and minerals
- The xylem walls are also heavily thickened by lignin, which prevents the leakage of water to surrounding cells
- This also provides mechanical strength to the plant
- The end walls of the xylem vessels dissolve at maturity, which form a continuous channel for the water
